Cash tills are used to store coins, notes and vouchers (e.g. coupons, chips or tokens) received by a retailer in exchange for goods or services. Some cash tills also have means for monitoring the transactions that are made using the till, and can provide the retailer with information regarding the total amount of cash that should be in the till. The retailer can use this information to make a comparison between the amount of cash that should be in the till and the amount of cash that is actually in the till. The retailer can, therefore, be made aware if there is a shortfall in the amount of cash in the till, which may indicate, for example, that a mistake has been made by a cashier or a that theft has taken place.
Traditionally, the amount of cash in a till was counted manually or using a separate cash counting machine. More recently, cash tills have been developed that have load cells for weighing the respective compartments within the cash till.
In these cash tills, each compartment is associated with a specific denomination of coin or note, or with a specific type of voucher. A load cell is used to determine the weight of the compartment to which it relates, and can provide a signal to a monitoring apparatus which can determine the amount of cash in the compartment based on the weight of that compartment. These tills are useful in that they provided a way to monitor the amount of cash in the till without the need to remove the cash from the till. These tills, however, have a number of drawbacks.
For example, load cells tend to suffer from random fluctuations or “jitter” in the signals that they output. Load cells can also suffer from a gradual increase or decrease or “drift” in the signals that they output over time. These effects can lead to incorrect calculations in the weight on the load cell, and consequently an incorrect determination of the amount of cash in the compartment to which the load cell relates.
Furthermore, a given compartment is not aware of the specific denomination of coin or note, or the type of voucher that it has received. Therefore, if a coin of one denomination (or some other object) is placed in a compartment that relates to a different denomination of coin, the monitoring apparatus is unaware that this has happened and an incorrect determination of the amount of cash in that compartment will be made due to the different weights of the different denominations.
Accordingly, the Applicants believe that there remains scope for improvements in taking readings from load cells and in monitoring cash till transactions.